Circular stapler and staple line reinforcement material

ABSTRACT

A surgical stapling instrument includes a staple cartridge assembly having a plurality of rows of staple receiving slots and an anvil assembly having a plurality of rows of staple forming recesses. The staple cartridge assembly, the anvil assembly, or both have one or more attachment members overmolded thereon. A staple line reinforcement material is attached to the attachment members.

CROSS REFERENCE TO RELATED APPLICATIONS

The present application is a Continuation application claiming thebenefit of and priority to U.S. patent application Ser. No. 13/094,893,filed on Apr. 27, 2011, the entire contents of which are incorporatedherein by reference.

BACKGROUND

1. Technical Field

The present application relates to surgical stapling and staple linereinforcement materials. In particular, the staple line reinforcementmaterial is attached to one or both tissue contacting surfaces of asurgical stapler utilizing a retainer.

2. Background

The use of staple line reinforcement materials, or buttresses, inconjunction with staplers is known. U.S. Pat. No. 5,542,594 to McKean etal., the disclosure of which is hereby incorporated by reference herein,discloses a surgical stapling apparatus with a biocompatible surgicalfabric attached to the apparatus. The surgical fabric and staples areattached to body tissue by the stapling apparatus. Pins or clips securethe fabric to surfaces of the stapling apparatus.

U.S. Pat. No. 7,128,748 discloses a circular stapler and buttress. Thebuttress material is positioned on the staple cartridge of the staplerand on the anvil component of the stapler. The anvil buttress materialhas a cylindrical raised center portion adapted to fit the centralrecessed aperture of the anvil and the staple cartridge buttress has acylindrical raised center portion adapted to fit a central recessedaperture in the cartridge component of the stapler.

U.S. Pat. No. 6,503,257 discloses an adhesive used to releasably attacha buttress material to clamping members of a stapler. The buttressmaterial is releasably attached by the adhesive material.

There is a need for a staple line reinforcement material or buttressmaterial attachment that does not complicate assembly or manufacturing,does not interfere with the operation of the surgical instrument, andsecurely attaches the material while allowing the material to bereliably released when desired.

SUMMARY

In an aspect of the present disclosure, a surgical stapling instrumentcomprises a staple cartridge assembly having a plurality of rows ofstaple receiving slots, an anvil assembly having an anvil memberdefining a plurality of rows of staple forming recesses. The staplecartridge assembly, the anvil assembly, or both, has one or moreattachment members. A staple line reinforcement material is attached tothe attachment members by ultrasonic welding.

In certain embodiments, the staple line reinforcement material definesperforations adjacent the attachment members. Such perforations can beuseful to facilitate release of the buttress from the surgical staplingapparatus. In certain embodiments, the surgical stapling instrument is acircular stapler. The plurality of rows of staple receiving slots can becircular rows. Such staplers are useful in intestinal anastomosisprocedures and other surgical procedures. The plurality of rows ofstaple forming recesses can be circular rows.

In certain embodiments, the one or more attachment members are formed onthe anvil member by molding plastic. The one or more attachment memberscan be disposed on the anvil member; the anvil member is made of metal,whereas the attachment members can made from plastic.

In certain embodiments, the one or more attachment members are disposedon the staple cartridge assembly outwardly of the rows of staplereceiving slots. The staple line reinforcement material can be attachedto the one or more attachment members and define perforations adjacentthe one or more attachment members. In this way, the staple linereinforcement material lifts away from the staple cartridge assembly,separating at the perforations. A margin of material remains on thestaple cartridge assembly.

In another arrangement, the one or more attachment members are disposedon the anvil assembly outwardly of the rows of staple forming recesses.The staple line reinforcement material is attached to the one or moreattachment members and defines perforations adjacent the one or moreattachment members.

The anvil assembly may include a hub attached to the anvil member. Theanvil assembly may include a shaft and further comprising a tubular bodyportion, the staple cartridge assembly being mountable in the tubularbody portion; the tubular body portion has a rod, the shaft of the anvilassembly being attachable to the shaft. The surgical staplinginstrument, in certain embodiments, comprises a handle assembly.

In another aspect of the present disclosure, a surgical staplinginstrument comprises a staple cartridge assembly having a plurality ofrows of staple receiving slots, an anvil assembly having a shaft and ananvil member; the anvil member defines a plurality of rows of stapleforming recesses. A retainer is engaged to the shaft, and a staple linereinforcement material attached to the anvil assembly by the retainer.

The surgical stapling instrument can be a circular stapler. Theplurality of rows of staple receiving slots can be circular rows,whereas the plurality of rows of staple forming recesses would becircular rows.

In certain embodiments, the retainer is circular in shape and has acentral aperture for receiving the shaft. The retainer may befrictionally engaged with the shaft. For example, the retainer is formedof a material that has a coefficient of friction with the shaft, thecoefficient of friction being selected so as to retain the retainer andthe staple line reinforcement material on the shaft.

In certain embodiments, the retainer is secured to the shaft utilizing afastener. Alternatively, the retainer is secured to the shaft utilizinga snap-fit relationship between the retainer and the anvil assembly. Theretainer, the shaft, or both, may be texturized in such a way so as toimprove the frictional engagement of those parts. For example, thesurface of the shaft is mechanically treated, or the shaft, theretainer, or both, have a coating that increases friction between theshaft and the retainer.

The anvil assembly may include a hub attached to the anvil member. Incertain embodiments, the surgical stapling instrument has a tubular bodyportion, the staple cartridge assembly being mountable in the tubularbody portion; the tubular body portion has a rod, the shaft of the anvilassembly being attachable to the shaft. In certain embodiments, thesurgical stapling instrument has a handle assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

An embodiment or embodiments of the presently disclosed surgicalinstrument and staple line reinforcement material is disclosed withreference to the drawings, wherein:

FIG. 1 is a perspective view of an embodiment of the present disclosureshowing including a circular stapling instrument;

FIG. 2 is perspective view of the circular stapling instrument of FIG. 1with the anvil assembly detached;

FIG. 3 is a perspective view of the circular stapling instrument ofFIGS. 1 and 2 with the anvil assembly attached;

FIG. 4 is a perspective view of a circular stapling instrument anvilassembly, staple line reinforcement material, and retainer, with partsseparated, according to the embodiment of FIGS. 1 through 3;

FIG. 5 is an elevation view of a staple line reinforcement materialretainer assembly according to the embodiment of FIGS. 1 through 4;

FIG. 6 is a staple line reinforcement material retainer assemblyaccording to a further embodiment of the present disclosure;

FIG. 7 is a plan view of a prior art circular stapling instrument anvilmember;

FIG. 8 is a plan view of a circular stapling instrument anvil memberaccording to a further embodiment of the present disclosure;

FIG. 9 is a detail of FIG. 7 showing attachment tabs;

FIG. 10 is a plan view of a ring having attachment member tabs inaccordance with a further embodiment of the present disclosure;

FIG. 11 is a partial perspective view of a circular stapling instrumentbody portion and cartridge assembly in accordance with anotherembodiment;

FIG. 12 is a plan view of a ring having attachment member tabs inaccordance with the embodiment of FIG. 11;

FIG. 13 is a perspective view of a staple line reinforcement material inaccordance with a further embodiment of the present disclosure;

FIG. 14 is perspective view of a linear surgical stapling instrumentaccording to another embodiment of the present disclosure;

FIG. 15 is a perspective view of a staple cartridge assembly inaccordance with the embodiment of FIG. 14;

FIG. 16 is a perspective view of an anvil member in accordance with theembodiment of FIGS. 14 through 15;

FIG. 17 is a perspective view of a staple line reinforcement material inaccordance with the embodiment of FIGS. 14 through 16;

FIG. 18 is a plan view of a ring or frame having attachment member tabsin accordance with the embodiment of FIGS. 14 through 17;

FIG. 19 is a perspective view of a staple line reinforcement material inaccordance with an embodiment of the present disclosure; and

FIG. 20 is a perspective view of a staple line reinforcement material inaccordance with a further embodiment of the present disclosure.

DETAILED DESCRIPTION

An embodiment or embodiments of the presently disclosed staplinginstrument, retainer, and staple line reinforcement material will now bedescribed in detail with reference to the drawings. Like numerals in thedrawings designate identical or corresponding elements in each of theseveral views. As is common in the art, the term “proximal” refers tothat part or component that is closer to the user of the instrumentwhile the term “distal” refers to that part or component that is fartherfrom the user of the instrument.

FIG. 1 illustrates a circular surgical stapling instrument which isgenerally designated as 10. Surgical stapling instrument 10 includes ahandle assembly 12 having at least one pivotable actuating handle 14 anda rotatable actuator 18. A tubular body portion 20 extends from thehandle assembly 12. The tubular body portion 20, which generally has acircular cross-sectional shape, may have a straight or a curved shapealong its length and may be flexible or relatively rigid.Cross-sectional shapes other that circular are contemplated, so that thetubular body portion 20 can have a polygonal, elliptical, semi-circular,ovoid, or other shape. The body portion 20 terminates in a staplecartridge assembly 22 which includes a distally facing tissue contactingsurface defining one or more rows 37 of staple receiving slots 36. Eachstaple receiving slot has a staple (not shown) disposed therein.Typically, a pair of circular rows 37 of staple receiving slots 36 isprovided, although other shapes, such as annular, are contemplated. Ananvil assembly 30 is positioned distally of the staple cartridgeassembly 22, which includes an anvil member 26 and an anvil shaft 28operatively associated therewith. The anvil assembly has a proximallyfacing tissue contacting surface that defines staple forming recesses 27that correspond to the circular rows of staple receiving slots. Thetubular body portion 20 has a corresponding rod or shaft 40 centrallylocated with respect to the staple cartridge assembly 22. The shaft 28of the anvil assembly is removably connectable to the rod or shaft 40 ofthe tubular body portion 20. The anvil shaft defines a longitudinal axis“x”.

The staple cartridge assembly 22 is connectable to the distal end oftubular body portion 20 or may be configured to concentrically fitwithin the distal end of tubular body portion 20. Typically, staplecartridge assembly 22 includes a staple pusher (not shown) with a distalportion defining two concentric rings of peripherally spaced fingers(not shown), each one of which is received within a respective staplereceiving slot 36. Typically, a knife (not shown) having a cutting edgeis disposed within the staple cartridge assembly 22. The knife edge iscircular and disposed radially inward of the rows of staples. The knifeis mounted so that as the staple pusher is advanced axially in thedirection of the anvil assembly, the knife is also advanced axially.Alternatively, the knife may be separately actuated. The staple pusheris advanced in the distal direction to drive staples from the staplereceiving slots 36 against the anvil member so that the staple formingrecesses 27 form the staples in a closed shape. The knife is advancedand driven toward the anvil assembly 30 to cut tissue. U.S. Pat. No.5,915,616 to Viola et al., the entire content of which is herebyincorporated herein by reference, discloses a circular staplinginstrument. Although a circular stapling instrument is shown in FIG. 1,the stapling device may be arranged to deploy staples in asemi-circular, linear, or other desired shape. Although discussed withreference to intestinal tissue, devices according to the presentdisclosure can be arranged to join and/or treat other tissues in otherprocedures.

The anvil member 26 may or may not be pivotable about the anvil shaft 28from a first, initial position in which a plane defined by the tissuecontact surface 52 of the anvil member 26 is substantially perpendicularto the longitudinal axis of the anvil shaft 28 to a second position,tilted with respect to the longitudinal axis “x”. The second position isdesirably a reduced profile position in which anvil member 26 defines anangle with respect to the longitudinal axis “x”. Alternately, the anvilmember 26 is rigidly attached to the anvil shaft 28.

The anvil shaft 28 is dimensioned to releasably engage an anvil retainer(not shown) on the rod or shaft 40 of a circular surgical staplinginstrument, such as the surgical stapling instrument 10. One suchsurgical stapling device having an anvil retainer and with which anvilassembly 30 may be used is disclosed in U.S. provisional patentapplication Ser. No. 60/281,259, filed Apr. 3, 2001, (“the '259application”) which is hereby incorporated by reference herein, in itsentirety. The anvil retainer functions to align anvil assembly 30 withthe body portion 20 (FIG. 1) of the surgical stapling instrument 10during movement of the anvil assembly 30 from a positioned spaced fromthe staple cartridge assembly 22 of the surgical stapling device to anapproximated position in close alignment with the staple cartridgeassembly 22.

The circular stapling instrument can be used to form an anastomosisbetween sections of intestinal tissue. As shown in FIGS. 2 and 3, theanvil assembly 30 is detached from the rod or shaft 40 of the tubularbody portion 20 and a section of tubular body vessel, such as a sectionof intestine, is secured to the anvil assembly 30, typically by tying asuture “P” around the shaft 28 of the anvil assembly 30. Another sectionof tubular tissue is secured to the tubular body portion 20 by tying asuture around the shaft 40. See FIG. 2. The shaft 28 is then connectedto the shaft 40. The actuator 18 is rotated to withdraw the shafts 28,40 thereby approximating the anvil assembly 30 with the staple cartridgeassembly 22. To fire the staples, the actuating handles 14 are squeezed,which advances the staple pusher and the knife (not shown). The staplespass through each section of tubular tissue and are formed against theanvil so that the sections of tubular tissue are joined to one another.The knife cuts the tissue radially inward of the rows of staples, andthe sutured material is removed with the circular stapling device.

According to the present disclosure, a surgical stapling instrument hasa staple line reinforcement material retained thereon. In certainembodiments, the anvil head 42 has an inner recess 53 that is generallyannular and may include a cut ring for receiving the knife. As shown inFIG. 4, a staple line reinforcement material 50 has a central aperture51 for receiving the anvil shaft 28 and is dimensioned so that thestaple line reinforcement material overlies the staple forming recesses27 of the anvil member 26 when the staple line reinforcement material isplaced on the shaft 28. A small amount of excess material may lie overthe outside edge of the anvil member. A retainer 60, which may be shapedas a washer with a central aperture 61, has an outside diameter slightlyless than the inside diameter of the knife so that the retainer does notinterfere with cutting. The inside diameter is dimensioned to receivethe anvil shaft and be frictionally retained on the shaft. FIG. 5 showsthe staple line reinforcement material retainer assembly 66. When thestaple line reinforcement material is placed on the anvil shaft 28 andthe retainer 60 is then placed on the anvil shaft 28 over the stapleline reinforcement material, the frictional engagement between theretainer 60 and the shaft keep the staple line reinforcement material inplace during use. The retainer 60 may be formed of a material that has adesired coefficient of friction with the shaft, which is normally metal,such as stainless steel.

In another embodiment, the retainer is secured to the anvil assemblyutilizing a fastener (such as a screw or bolt), a clip, a detent, or bya snap-fit relationship between the retainer and the anvil assembly. Ina further alternative, the retainer 60, the shaft 28, or both, may betexturized 69, 29, respectively, in such a way so as to improve thefrictional engagement of those parts. This can include mechanicallytreating the surfaces of the shaft and/or retainer, or can includecoatings.

During use, the rotatable actuator 18 is manipulated to approximate theanvil assembly 30 toward the staple cartridge assembly 22 and clamptissue therebetween. When the pivotable actuating handle 14 is moved,the knife and/or pusher will be moved in a direction toward the anvilassembly to fire the staples and cut tissue. The staple linereinforcement material retainer assembly 66 is arranged so that theretainer 60 lies inwardly of the knife. The retainer retains the stapleline reinforcement material 50 against the tissue contacting surface 52of the anvil member 26. The knife will cut the tissue and the stapleline reinforcement material, making the retainer easy to remove with thecircular stapling instrument 10.

In another embodiment of the present disclosure, a circular staplinginstrument as discussed above in connection with FIGS. 1 through 3 hasan anvil assembly 130 with an anvil member 126 attached to an anvil head142. The anvil assembly 130 further includes an anvil shaft 128attachable to the rod or shaft 40. A typical prior art anvil member 125is shown in FIG. 7 and has two rows of staple forming recesses 127formed in the tissue contact surface 152 of the anvil member 125. Ananvil member 126 according to an embodiment of the present disclosure isshown in FIG. 8. Attachment members 132, which may be formed as tabs,are attached to the anvil member 126 so that the attachment members 132are generally flush with the tissue contact surface 152. Recessed orprotruding attachment members are also contemplated. In this way, theanvil member 126 can be formed from a material that is useful fordefining staple forming recesses therein and for forming staples. Thus,typically the anvil member is formed from a metal such as stainlesssteel. The attachment members 132 are formed from a material that isuseful for attachment to a staple line reinforcement material. Thestaple line reinforcement material 50 is attached to the attachmentmembers utilizing adhesives, ultrasonic or other kinds of welding, orother methods. The attachment member or members 132 may be formed of avariety of polymeric materials, such as the polymeric materials fromwhich the staple line reinforcement material is made. In one example,recesses are formed in the anvil member, as by grinding, drilling,machining, etc. A polymeric material is overmolded on the anvil memberso that attachment members of the polymeric material are disposed in therecesses. In a further embodiment, a plastic frame or ring 141 havingtabs extending inwardly (see FIG. 10) is attached to the anvil member,either before or after the assembly of the anvil member 126 with theanvil head 142. The tabs are snapped into place in preformed recesses inthe anvil member. Alternately, the frame or ring 141 is attached to theanvil member so that the tab or tabs are disposed adjacent the tissuecontact surface 152 but outside of the staple forming recesses 127. Inanother embodiment, the plastic ring may be used, without tabs, so thatthe staple line reinforcement material is attached at the ring.

One or more attachment members 132 may be used and they may have avariety of shapes. The tabs shown in FIG. 9 are generally trapezoidal inshape and are disposed between the staple forming recesses of the anvilmember as shown in FIG. 8. The attachment members/tabs do not interferewith the formation of the staples in the staple receiving recesses.

It may be desirable to attach a staple line reinforcement material 50adjacent the staple cartridge assembly 22. As shown in FIG. 11, thestaple cartridge assembly 22 has a central recess 24 through which therod or shaft 40 (which has been omitted for clarity) passes. Anattachment member or attachment members 232, which may be formed astabs, are attached to the tissue contact surface 25 of the cartridgeassembly 22. The attachment members 232 may be formed so that they aregenerally flush with the tissue contact surface 25, but recessed orprotruding attachment members are contemplated. The attachment member ormembers are formed from a material useful for attachment to the stapleline reinforcement material. The staple line reinforcement material 50is attached to the attachment members utilizing adhesives, ultrasonic orother kinds of welding, or other methods. The attachment members 232 maybe formed from a variety of polymeric materials, such as the polymericmaterials from which the staple line reinforcement material is made. Inone example, recesses are formed in the staple cartridge tissue contactsurface 25 and a polymeric material is overmolded on the staplecartridge in the recesses. In this way, the material of the staplecartridge can be different from the material for attaching the stapleline reinforcement material. In other embodiment, a plastic frame orring 241 (FIG. 11) having tabs extending inwardly is attached to thestaple cartridge so there the tabs are snapped into place in preformedrecesses. Alternately, the frame or ring 241 is attached to thecartridge assembly or to the body portion 20 so that the tab or tabs aredisposed on the tissue contact surface 25 but lie outwardly of thestaple slots 36. In another embodiment, the plastic ring may be used,without tabs, so that the staple line reinforcement material is attachedat the ring.

Alternately, the material of the staple cartridge 23, which is normallyplastic, can be selected so as to be useful for attaching the stapleline reinforcement material by adhesives, ultrasonic or other kinds ofwelding, or other methods. In certain embodiments, the anvil assembly130 includes a cut ring disposed in the recess 153. The cut ring can beformed with tabs extending proximally toward the tissue contact surface152 so as to be accessible for attachment to the staple linereinforcement material.

In the embodiments discussed in connection with FIGS. 6 through 12, thestaple line reinforcement material 50 can be dimensioned to have aninner diameter that is smaller than the diameter of the knife of thecircular stapling instrument. When the knife is actuated, a portion ofthe staple line reinforcement material is removed. This may tend toincrease the firing forces for the circular stapling instrument.Alternately, the staple line reinforcement material 50 can bedimensioned to have an inner diameter that is larger than the diameterof the knife of the circular stapling instrument so that the knife doesnot cut the staple line reinforcement material. When the staple firingis actuated, the staples hit the staple line reinforcement material,passing through the staple line reinforcement material. The staples thatimpact near the weld or other attachment points apply enough force tosubstantially break the connection between the staple line reinforcementmaterial and the attachment member or attachment members. The stapleline reinforcement material is thereby released. Alternately, the gentlemanipulation of the circular stapling instrument can be relied upon togently separate the staple line reinforcement material from theattachment points.

In another embodiment of the present disclosure, a surgical staplinginstrument and staple line reinforcement material according to FIGS. 1through 3 and 6 through 12 has a staple line reinforcement material 50 aattached to an attachment member or attachment members 132 disposed atthe tissue contacting surface 52 of the anvil assembly and/or disposedat the tissue contact surface 25 of the staple cartridge assembly 22.The attachment member or members 132 are formed from a material that isuseful for attaching the staple line reinforcement material 50 a. Thestaple line reinforcement material 50 a is attached to the attachmentmember or attachment members 132 permanently, so that the material 50 isnot intended to be releasable when the staples are fired or theinstrument is manipulated in removing the instrument from the surgicalsite. The staple line reinforcement material includes perforations 68,or areas of weakness, adjacent the attachment member or members. SeeFIG. 19. The inner diameter of the staple line reinforcement material 50a is larger than the diameter of the knife. Desirably, the attachmentmember or attachment members 132 lie outwardly of the staple formingrecesses 27 of the anvil assembly 30 and/or outwardly of the staplereceiving slots 36 of the staple cartridge assembly 22. The perforations68 are disposed inwardly of the attachment member or members 132, butoutwardly of the knife. In use, the anvil assembly will be approximatedwith the staple cartridge assembly to clamp tissue, and the staples willbe fired and the knife deployed. Upon removal of the staplinginstrument, the staple line reinforcement material 50 a will separatefrom the anvil assembly and/or cartridge assembly at the perforations. Amargin of material will remain with the anvil assembly and/or cartridgeassembly.

In another embodiment, the staple line reinforcement material 50 a hasan inner diameter that is smaller than the diameter of the knife so thata portion of the staple line reinforcement material 50 a is severedremoved by the knife.

In another embodiment of the present disclosure a linear staplinginstrument is used with a staple line reinforcement material on theanvil, the cartridge assembly, or both. The linear stapling instrument300 has stapler jaws 310, 320. See FIG. 14. The stapler jaw 310 is astaple cartridge assembly having one or more rows 337 of staplereceiving slots 336. Each staple receiving slot has a staple (not shown)disposed therein. Typically, three linear rows 337 of staple receivingslots 336 are provided on either side of a channel 339. The other jaw isan anvil assembly 320 positioned in opposition to the staple cartridgeassembly 310 and pivotably mounted so that the anvil assembly and staplecartridge assembly can be approximated to clamp tissue therebetween. Theanvil assembly includes an anvil member 326 defining a plurality ofstaple forming recesses 331 that correspond to the linear rows 337 sothat the stapling instrument forms linear staple lines. The staplingjaws 310, 320 are disposed at a distal end of an endoscopic shaft 340. Ahandle assembly 301 includes a pivotable handle 303 that drives movementof a drive member through the staple cartridge assembly 310. The drivemember (not shown) passes through the channel 339 and pushes a sled orcamming bar through the staple cartridge to drive staple pushers, andthe staples, through the slots 336 toward the staple forming recesses ofthe anvil member 326. Certain embodiments of such a surgical instrumentis disclosed in U.S. Pat. No. 6,241,139 to Milliman et al., thedisclosure of which is hereby incorporated by reference herein, in itsentirety.

To attach the staple line reinforcement material to the jaw or jaws 310,330, attachment members are formed on or in the cartridge assembly 310and/or anvil assembly 330. Typically the anvil member 326 is formed froma metal such as stainless steel. The attachment members 332 are formedfrom a material that is useful for attachment to a staple linereinforcement material. The staple line reinforcement material 350 isattached to the attachment members 332 utilizing adhesives, ultrasonicor other kinds of welding, or other methods. The attachment member ormembers 332 may be formed of a variety of polymeric materials, such asthe polymeric materials from which the staple line reinforcementmaterial is made. In one example, recesses are formed in the anvilmember, as by grinding, drilling, machining, etc. A polymeric materialis overmolded on the anvil member so that attachment members of thepolymeric material are disposed in the recesses. In one embodiment, theattachment members 332 include a first distal attachment member 332 a, asecond distal attachment member 332 b, a first proximal attachmentmember 332 c, and a second proximal attachment member 332 d, so thatthere are one or more attachment members at each of the distal andproximal ends of the anvil member. See FIG. 16.

In a further embodiment, a plastic frame or ring 341 having tabs 342extending inwardly (see FIG. 18) is attached to the anvil member, eitherbefore or after the assembly of the anvil member 326 in the anvilassembly. The tabs are snapped into place in preformed recesses in theanvil member. Alternately, the frame or ring 341 is attached to theanvil member so that the tab or tabs are disposed adjacent the tissuecontact surface 352 but outside of the staple forming recesses 327. Inanother embodiment, the plastic frame or ring may be used, without tabs,so that the staple line reinforcement material is attached at the ring.

It may be desirable to attach a staple line reinforcement material tothe tissue contact surface 311 of the cartridge assembly 310. Attachmentmembers 334 are provided for the staple cartridge assembly and areformed from a material that is useful for attachment to a staple linereinforcement material. The staple line reinforcement material 350 isattached to the attachment members 334 utilizing adhesives, ultrasonicor other kinds of welding, or other methods. The attachment member ormembers 334 may be formed of a variety of polymeric materials, such asthe polymeric materials from which the staple line reinforcementmaterial is made. The attachment member or members 334 can be made byproviding recesses in the tissue contact surface 311 of the cartridgeassembly 310, and overmolding. Alternately, a plastic frame or ring,like that shown in FIG. 18 may or may not include tabs and provides asurface at which to attach the staple line reinforcement material usingadhesives, ultrasonic or other welding, and other methods.Alternatively, the material of the staple cartridge can be selected soas to be useful for attaching the staple line reinforcement material.

In another embodiment of the present disclosure, a surgical staplinginstrument and staple line reinforcement material according to FIGS. 14through 18 has a staple line reinforcement material 350A attached to anattachment member or attachment members 332 disposed at the tissuecontacting surface of the anvil assembly 320 and/or attachment member ormembers 334 disposed at the tissue contact surface of the staplecartridge assembly 310. The attachment member or members 332, 334 areformed from a material that is useful for attaching the staple linereinforcement material 350A. The staple line reinforcement material 350Ais attached to the attachment member or attachment members 332, 334permanently, so that the material 350A is not intended to be releasablewhen the staples are fired or the instrument is manipulated in removingthe instrument from the surgical site. The staple line reinforcementmaterial includes perforations 368, or areas of weakness, adjacent theattachment member or members 332, 334. See FIG. 20. Desirably, theattachment member or attachment members 332, 334 lie outwardly of therows 337 of staple forming recesses 331 of the anvil assembly 30 and/oroutwardly of the rows 337 of the staple receiving slots 336 of thestaple cartridge assembly 310. The perforations are disposed inwardly ofthe attachment member or members 332, 334, but outwardly of the rows 337staple forming recesses 331 of the anvil assembly 30 and/or outwardly ofthe rows 337 of the staple receiving slots 336. In use, the anvilassembly will be approximated with the staple cartridge assembly toclamp tissue, and the staples will be fired and the knife deployed. Uponremoval of the stapling instrument, the staple line reinforcementmaterial 350A will separate from the anvil assembly and/or cartridgeassembly at the perforations. A margin of staple line reinforcementmaterial remains with the surgical stapling instrument.

It is contemplated that the staple line reinforcement materialsdiscussed above may be fabricated from or include a surgical grade,biocompatible, non-absorbable material and may comprise a mesh. Forexample, the staple line reinforcement material may be fabricated from“TEFLON”, which is a registered trademark owned by DuPont de Nemours &Co. It is further contemplated that body portion 102 may be fabricatedfrom a biocompatible polymeric foam, felt, polytetrafluoroethylene(ePTFE), gelatin, fabric or the like, or any other biocompatiblematerial.

Non-absorbable materials used for staple line reinforcement materialinclude, and are not limited to, those that are fabricated from suchpolymers as polyethylene, polypropylene, nylon, polyethyleneterephthalate, polytetrafluoroethylene, polyvinylidene fluoride, and thelike. Further non-absorbable materials include and are not limited tostainless steel, titanium and the like.

In one embodiment, the staple line reinforcement material may befabricated from a bio-absorbable material. In other embodiments, thestaple line reinforcement material has at least one portion that isabsorbable and at least one portion that is not absorbable.Bio-absorbable materials used for staple line reinforcement materialinclude, and are not limited to, those fabricated from homopolymers,copolymers or blends obtained from one or more monomers selected fromthe group consisting of glycolide, glycolic acid, lactide, lactic acid,p-dioxanone, a-caprolactone and trimethylene carbonate. Otherbio-absorbable materials include and are not limited to, for example,Polyglycolic Acid (PGA) and Polylactic Acid (PLA). In one embodiment,the staple line reinforcement material may be fabricated frombio-absorbable felt, gelatin or any other bio-absorbable materials.

The staple line reinforcement material can incorporate a wound treatmentmaterial, which includes and is not limited to one or a combination ofadhesives, hemostats, sealants, coagulants, astringents, andmedicaments. Other surgically biocompatible wound treatment materialswhich may be employed in or applied by surgical instruments, includingsurgical staplers, include adhesives whose function is to attach or holdorgans, tissues or structures; sealants to prevent fluid leakage;hemostats to halt or prevent bleeding; coagulants, astringents (e.g.,sulfates of aluminum) and medicaments. Examples of adhesives which canbe employed include protein derived, aldehyde-based adhesive materials,for example, the commercially available albumin glutaraldehyde materialssold under the trade designation BioGlue™ by Cryolife, Inc., andcyanoacrylate-based materials sold under the trade designationsIndermil™ and Derma Bond™ by Tyco Healthcare Group, LP and EthiconEndosurgery, Inc., respectively. Examples of sealants, which can beemployed, include fibrin sealants and collagen-based and syntheticpolymer-based tissue sealants. Examples of commercially availablesealants are synthetic polyethylene glycol-based, hydrogel materialssold under the trade designation CoSeal™ by Cohesion Technologies andBaxter International, Inc. Examples of hemostat materials, which can beemployed, include fibrin-based, collagen-based, oxidized regeneratedcellulose-based and gelatin-based topical hemostats. Examples ofcommercially available hemostat materials are fibrinogen-thrombincombination materials sold under the trade designations CoStasis™ byTyco Healthcare Group, LP, and Tisseel™ sold by Baxter International,Inc. The wound treatment material can include medicaments. Medicamentsmay include one or more medically and/or surgically useful substancessuch as drugs, enzymes, growth factors, peptides, proteins, dyes,diagnostic agents or hemostasis agents, monoclonal antibodies, or anyother pharmaceutical used in the prevention of stenosis.

The staple line reinforcement material may include a single layerincluding a homogeneous array of bio-absorbable or non-absorbablematerials or a heterogeneous array of bio-absorbable and/ornon-absorbable materials. The staple line reinforcement material mayinclude a layered body portion having at least two layers as indicatedby first layer, film or wafer and second layer, film or wafer. In thisembodiment, each layer may include a homogeneous or heterogeneous arrayof bio-absorbable and/or non-absorbable materials.

In certain preferred embodiments, the staple line reinforcement materialis a non-woven fabric. The non-woven fabric can be formed utilizing amelt blown process, including the following steps. The polymer resin ismelt extruded. A melt pump meters out the molten polymer to a die headhaving an array of holes. By way of example, the holes have a diameterof between about 0.175 and about 0.25 millimeters. The polymer is forcedthrough the array of holes in the die. Polymer fibers exit the die andare forced onto a conveyor belt. A stream of blowing hot air can be usedto force the polymer fibers onto the conveyor. Suction through theconveyor belt surface can be used to compact the fibers against the beltand against each other, as the fibers cool. Additional compression maybe applied to the fibers, such as by using a calendaring roll, which mayinclude heating or cooling. The non-woven fabric may then be annealed.For example, isometric tension or other uniform compression can be usedto drive crystallization and remove the monomer. The polymer isdesirably a bioabsorbable or non-bioabsorbable polymer, such as aglycolide lactide copolymer (the material utilized in Polysorb™sutures), a termpolymer composed of glycolide, trimethylene carbonateand dioxanone (the material utilized in Biosyn™ sutures), a polymer ofglycolide, caprolactone, trimethylene carbonate, and lactide (thematerial utilized in Caprosyn™ sutures), and a glycolide trimethylenecarbonate copolymer (the material utilized in Maxon™ sutures).

In certain embodiments, the non-woven fabric is porous. For example, thenon-woven fabric can have a porousity of between about 50% and about90%. The fiber diameter may be between about 5 and about 100 μm. Thefabric thickness may be between about 150 and about 400 μm.

It will be understood that various modifications may be made to theembodiments disclosed herein. For example, the surgical staplinginstrument need not apply staples but rather may apply two partfasteners as is known in the art. Further, the length of the linear rowof staples or fasteners, or the length or diameter of a circular row ofstaples or fasteners, may be modified to meet the requirements of aparticular surgical procedure. Therefore, the above description shouldnot be construed as limiting, but merely as exemplifications ofpreferred embodiments. Those skilled in the art will envision othermodifications within the scope and spirit of the claims appendedthereto.

What is claimed is:
 1. A method of assembling a surgical staplinginstrument, the method comprising: providing a staple cartridge assemblyhaving a tissue contacting surface defining a plurality of rows ofstaple receiving slots therein; providing an anvil assembly including atissue contacting surface defining a plurality of rows of staple formingrecesses therein; providing an attachment member fabricated from apolymeric material; overmolding the attachment member onto the tissuecontacting surface of at least one of the staple cartridge assembly orthe anvil assembly; providing staple line reinforcement material; andsecuring the staple line reinforcement material to the attachmentmember.
 2. The method according to claim 1, further comprising formingrecesses in the tissue contacting surface of at least one of the staplecartridge assembly or the anvil assembly prior to overmolding, whereinthe attachment member is disposed in the recesses.
 3. The methodaccording to claim 2, wherein the polymeric material is plastic.
 4. Themethod according to claim 1, further comprising releasably attaching thestaple line reinforcement material to the attachment member byultrasonic welding.
 5. The method according to claim 1, wherein thestaple line reinforcement material defines perforations therein, themethod further including disposing the staple line reinforcementmaterial such that the perforations are adjacent the attachment member.6. The method according to claim 1, further comprising disposing theattachment member on the staple cartridge assembly at a locationoutwardly of the rows of staple receiving slots.
 7. The method accordingto claim 1, further comprising disposing the attachment member on theanvil assembly at a location outwardly of the rows of staple formingrecesses.
 8. The method according to claim 1, further comprisingdisposing the attachment member between adjacent staple forming recessesof the anvil assembly.
 9. The method according to claim 1, furthercomprising disposing the attachment member between adjacent staplereceiving slots of the staple cartridge assembly.
 10. The methodaccording to claim 1, wherein the surgical stapling instrument is acircular stapler.